Blood tests showed Tuporo's alcohol level was more than twice the legal limit and the police serious crash unit investigation put his speed as high as 122kmh at the time he lost control of his vehicle.

While travelling west down Neilson St at about 2.15am, he skidded on to the wrong side of the road before veering back.

But he could not right the Mitsubishi Lancer, mounted the kerb and hit a concrete power pole.

Emergency services were on the scene quickly but could not get to Tuporo because of fallen power cables.

Welsh told the inquest the live power lines were "draped over the vehicle" and he got as close as he could to establish the state of the driver.

"I saw his head in the rear passenger area but the rest of his body was not visible because the vehicle's interior had collapsed around him," Welsh said.

He asked Tuporo his name but only received strained noises in response.

It was only about 4.40am - nearly two and a half hours after the crash - that emergency services could safely access the wrecked car.

Tuporo was pronounced dead at the scene and was eventually extracted from the wreck at 6.40am.